Journal of General Internal Medicine

, Volume 26, Issue 6, pp 621–626 | Cite as

Financial Incentives for Extended Weight Loss: A Randomized, Controlled Trial

  • Leslie K. John
  • George Loewenstein
  • Andrea B. Troxel
  • Laurie Norton
  • Jennifer E. Fassbender
  • Kevin G. Volpp
Original Research

ABSTRACT

BACKGROUND

Previous efforts to use incentives for weight loss have resulted in substantial weight regain after 16 weeks.

OBJECTIVE

To evaluate a longer term weight loss intervention using financial incentives.

DESIGN

A 32-week, three-arm randomized controlled trial of financial incentives for weight loss consisting of a 24-week weight loss phase during which all participants were given a weight loss goal of 1 pound per week, followed by an 8-week maintenance phase.

PARTICIPANTS

Veterans who were patients at the Philadelphia Veterans Affairs Medical Center with BMIs of 30–40.

INTERVENTION

Participants were randomly assigned to participate in either a weight-monitoring program involving a consultation with a dietician and monthly weigh-ins (control condition), or the same program with one of two financial incentive plans. Both incentive arms used deposit contracts (DC) in which participants put their own money at risk (matched 1:1), which they lost if they failed to lose weight. In one incentive arm participants were told that the period after 24 weeks was for weight-loss maintenance; in the other, no such distinction was made.

MAIN MEASURE

Weight loss after 32 weeks.

KEY RESULTS

Results were analyzed using intention-to-treat. There was no difference in weight loss between the incentive arms (P = 0.80). Incentive participants lost more weight than control participants [mean DC = 8.70 pounds, mean control = 1.17, P = 0.04, 95% CI of the difference in means (0.56, 14.50)]. Follow-up data 36 weeks after the 32-week intervention had ended indicated weight regain; the net weight loss between the incentive and control groups was no longer significant (mean DC = 1.2 pounds, 95% CI, -2.58–5.00; mean control = 0.27, 95% CI, -3.77–4.30, P = 0.76).

CONCLUSIONS

Financial incentives produced significant weight loss over an 8-month intervention; however, participants regained weight post-intervention.

KEY WORDS

behavioral medicine obesity psychology randomized trials behavioral economics 

REFERENCES

  1. 1.
    Ogden C, Carroll M, Curtin L, McDowell M, Tabak C, Flegal K. Prevalence of overweight and obesity in the United States. J Am Med Assoc. 2006;393(15):1549–55.CrossRefGoogle Scholar
  2. 2.
    Jeffery RW, Thompson PD, Wing RR. Effects on weight reduction of strong monetary contracts for calorie restriction or weight loss. Behav Res Ther. 1978;16(5):363–9.PubMedCrossRefGoogle Scholar
  3. 3.
    Jeffery R, Drewnowski A, Epstein L. Long-term maintenance of weight loss. Health Psychol. 2000;19(1 Suppl):5–16.PubMedCrossRefGoogle Scholar
  4. 4.
    NIH. (United States Department of Health and Human Services). NIH Guide: Findings of Scientific Misconduct. 2001 December 13, 2001.Google Scholar
  5. 5.
    Heshka S, Anderson J, Atkinson R, et al. Weight loss with self-help compared with a structured commercial program: a randomized trial. J Am Med Assoc. 2003;2003(289):14.Google Scholar
  6. 6.
    Loewenstein G, Brennan T, Volpp KG. Asymmetric paternalism to improve health behaviors. J Am Med Assoc. 2007;298(20):2415–7.CrossRefGoogle Scholar
  7. 7.
    Volpp K, John L, Troxel AB, Norton L, Fassbender J, Loewenstein G. Financial incentive-based approaches for weight loss: a randomized trial. J Am Med Assoc. 2008;300(22):2631–7.CrossRefGoogle Scholar
  8. 8.
    Kahneman D, Tversky A. Prospect theory: an analysis of decision making under risk. Econometrica. 1979;47:263–91.CrossRefGoogle Scholar
  9. 9.
    Ryan D, Espeland M, Foster G, et al. Look AHEAD (Action for Health in Diabetes): design and methods for a clinical trial of weight loss for the prevention of cardiovascular disease in type 2 diabetes. Control Clin Trials. 2003;24(5):610–28.PubMedCrossRefGoogle Scholar
  10. 10.
    Ariely D, Wertenbroch K. Procrastination, deadlines, and performance: self-control by precommitment. Psychol Sci. 2002;13(3):219–24.PubMedCrossRefGoogle Scholar
  11. 11.
    Knowler WC, Barrett-Connor E, Fowler SE, et al. Reduction in the incidence of type 2 diabetes with lifestyle intervention or metformin. N Engl J Med. 2002;346(6):393–403.PubMedCrossRefGoogle Scholar
  12. 12.
    Svenson O, Fischhoff B, MacGregor D. Perceived driving safety and seatbelt usage. Accident Analysis & Prevention. 1985;17(2):119-133.Google Scholar
  13. 13.
    Weinstein ND. Unrealistic optimism about susceptibility to health problems: Conclusions from a community-wide sample Journal of Behavioral Medicine. 1987;10(5):1573-3521.Google Scholar
  14. 14.
    Tversky A, Kahneman D. Loss aversion in riskless choice: a reference-dependent model. Q J Econ. 1991;106(4):1039–61.CrossRefGoogle Scholar
  15. 15.
    Ainslie G. Specious reward: a behavioral theory of impulsiveness and impulse control. Psychol Bull. 1975;82:463–96.PubMedCrossRefGoogle Scholar
  16. 16.
    Thaler RH. Some empirical evidence on time inconsistency. Rev Econ Stud. 1981;23:165–80.Google Scholar
  17. 17.
    Loewenstein G, Prelec D. Anomalies in intertemporal choice: evidence and an interpretation. Q J Econ. 1992;107:573–97.CrossRefGoogle Scholar
  18. 18.
    Kirby K. Bidding on the future: evidence against normative discounting of delayed rewards. J Exp Psychol Gen. 1997;126:54–70.CrossRefGoogle Scholar
  19. 19.
    Griffin D, Buehler R. Frequency, probability, and prediction: easy solutions to cognitive illusions? Cogn Psychol. 1999;38:48–78.PubMedCrossRefGoogle Scholar
  20. 20.
    Locke EA, Latham GP.A theory of goal setting and task performance Englewood Cliffs. NJ: Prentice Hall; 1990.Google Scholar

Copyright information

© Society of General Internal Medicine 2011

Authors and Affiliations

  • Leslie K. John
    • 1
  • George Loewenstein
    • 1
    • 2
  • Andrea B. Troxel
    • 2
    • 3
  • Laurie Norton
    • 2
    • 4
    • 5
  • Jennifer E. Fassbender
    • 3
  • Kevin G. Volpp
    • 2
    • 4
    • 5
    • 6
  1. 1.Department of Social and Decision SciencesCarnegie Mellon UniversityPittsburghUSA
  2. 2.Center for Health IncentivesLeonard Davis Institute of Health Economics, University of PennsylvaniaPhiladelphiaUSA
  3. 3.Center for Clinical Epidemiology and Biostatistics and Department of Biostatistics and EpidemiologyUniversity of PennsylvaniaPhiladelphiaUSA
  4. 4.Center for Health Equity Research and PromotionPhiladelphia Veterans Affairs Medical CenterPhiladelphiaUSA
  5. 5.Department of MedicineUniversity of Pennsylvania School of MedicinePhiladelphiaUSA
  6. 6.Department of Health Care ManagementThe University of Pennsylvania Wharton SchoolPhiladelphiaUSA

Personalised recommendations